In member function 'void Vector3Array::insert(Vector3)',
    inlined from 'int main()' at /in/foo.cc:62:17:
/in/foo.cc:38:14: warning: 'v.Vector3Array::n' may be used uninitialized [-Wmaybe-uninitialized]
   38 |         data[n++] = v;
      |              ^
/in/foo.cc: In function 'int main()':
/in/foo.cc:58:18: note: 'v' declared here
   58 |     Vector3Array v(n);
      |                  ^